This section is intended to introduce the reader to various aspects of art that may be related to various aspects of the present technique, which are described and/or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present technique. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.
Aspects of the present technique relate to an assembly for use in the control and/or the measurement of the flow of a fluid in a conduit.
A range of assemblies are known for controlling the flow of a fluid through a conduit and include a range of valves, such as gate valves, ball valves and butterfly valves, as well as a range of choke assemblies. These known assemblies rely on the use of one or more moveable mechanical components to vary the cross-sectional area of the flow path available to the fluid through the assembly. For example, a gate valve comprises a valve gate moveable between a closed position, in which the flow path through the gate valve is closed preventing fluid flow therethrough, and an open position, in which the flow path through the valve is open allowing the full flow of fluid therethrough. A common form of choke assembly comprises a cage having openings in the wall thereof, through which the fluid flowing through the choke is caused to flow. A closure member, for example a plug or sleeve disposed within the cage, is moveable with respect to the cage and may be positioned to cover some, all or none of the openings in the choke. In this way, the position of the closure member relative to the cage controls the number of openings available for the flow of fluid and, hence, the cross-sectional area available for fluid flow through the choke assembly.
The aforementioned assemblies rely on moveable components for changing the cross-sectional area available for the flow of a fluid through the assembly, as noted. As a consequence, one or more components of the assembly are exposed to the flowing fluid. For example, in a gate valve, the gate is exposed to the flow of fluid in any position other than the fully open or fully closed position. Similarly, in a choke assembly, the moveable closure member, such as the plug or sleeve, is contacted by the fluid flowing through the assembly. As a result, these components are subjected to wear and erosion by the flowing fluid. The rate of wear and erosion is particularly high when the fluid stream is a multiphase fluid stream, especially when the fluid stream contains entrained solid material. An example of such a multiphase fluid stream is the fluid produced from a subterranean well, which typically comprises a gaseous phase, one or more liquid phases, such as oil and water, and entrained solids, such as sand, gravel and debris from the well.
There is a need for an improved assembly to control the flow of fluid in a conduit. It would be advantageous if the assembly could handle a wide range of fluid streams, in particular erosive fluid streams, such as those produced from subterranean wells, with minimum wear on the components of the assembly. It would also be advantageous if the assembly could provide for the measurement of the fluid flow in the conduit, in addition to the control of the fluid flow.